I enjoy my K3.3, but it's been in a precarious position since I got an Olympus OM-1 and several lenses. No MFT camera can take the place of my K-1, but as for the K-3 lll's strengths -- smaller, lighter, quicker to focus and fire - the Oly does those things even better. Its IQ is fine, with similar sharpness to the K-3 but a stop less DR, which I miss.
I'm keeping it for now, but if I had to sell a camera, it would be the one.